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arXiv · 2611.04232

Galois-modular obstructions to the categorification of near-group fusion rings

Víctor Blasco
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Abstract

In this article we establish new obstructions to the categorification of near-group fusion rings by combining the values of irreducible characters of the Grothendieck ring with the Galois symmetry of the induced unit object $I(1)$ in the Drinfeld center. As a result, we show that a near-group ring of type $G+m$, where $G$ is an abelian group and both $|G|$ and $m$ are odd, can only categorify if $m=|G|$.

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Víctor Blasco. 2026-11-03. Galois-modular obstructions to the categorification of near-group fusion rings. https://arxiv.org/abs/2611.04232

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